β-Selective Heck Reactions of Unprotected Allylamines Driven by Surface Charge of in situ-Formed Pd Nanoparticles

Abstract

The regioselectivity for insertion reactions of allylamines is almost exclusively biased towards γ-functionalization for internal alkenes. To expand the synthetic toolbox to access unique new allylamine structures, we've demonstrated how controlling the surface charge of in situ-generated Pd nanoparticle catalysts can be exploited to achieve highly selective β-functionalization of internal allylamine substrates. A key to the regioselectivity switch is the decreased activation of the olefin by the less charged catalyst, allowing substrate electronic contributions to help dictate the product regiochemistry.